Abstract
Eight years of nut data collected on 934 juvenile black walnut trees clearly demonstrates the value of mass selection as a means of increasing nut yields — number of nuts produced/tree/year ranged from 0 to 345. Furthermore, high variability in percentage kernel crackout and nut weight was observed in 130 select trees. Selection on the basis of these characteristics has the potential to lead to a several-fold increase in the quantity of usable kernels produced per hectare. An additional 48% gain in nut production is demonstrated using late-summer fertilization with NPK (13-13-13). Increases in nut yields could provide substantial increases in profit for the landowner and an enhancement in an already economically viable land-use alternative for individuals interested in making the transition from a cropping system to trees.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Funk DT and Polak DJ (1978) Annual Report of Northern Nut Growers Assn 69: 63–65
Garrett HE, Jones JE, Haines JK and Slusher JP (1991) Black walnut nut production under alleycropping management: an old but new cash crop for the farm community. In: Garrett HE (ed) Proceedings of 2nd Conference on Agroforestry in North America, August 18–21, Springfield, Missouri, 403 pp
Garrett HE and Kurtz WB (1983) Silvicultural and economic relationships of integrated forestry-farming with black walnut. Agroforestry Systems 1: 245–256
Kozlowski TT, Kramer PJ and Pallardy SG (1991) The Physiological Ecology of Woody Plants. Academic Press Inc, 657 pp
Pellett HM and Carter JV (1981) Effect of nutritional factors on cold hardiness of plants. Hortic Rev 3: 144–171
Ponder F Jr (1976) Fertilization increases nut but not wood production of pole-sized black walnut. 67th Annual Report of the Northern Nut Growers Assn 67: 60–63
Pope PE, Holt HA and Chaney WR (1982) Interaction of nitrogen fertilization and chemical weed control on four-year volume growth of a black walnut plantation. In: Black walnut for the future, USDA Forest Service. General Technical Report NC-74, pp 105–109
Romas DE (1985) Walnut Orchard Management. Cooperative Extension, University of California, Publication #21410, 178 pp
Schlesinger RC and Funk DT (1977) Managers handbook for black walnut. General Technical Report NC-38 USDA, Forest Service, 22 pp
van Buijtenen JP, Donovan GA, Long EM, Lowe WJ, McKinley CR, Robinson JF and Woessner RA (1981) Introduction to practical forest tree improvement. Circular 107, Texas Forest Service, 22 pp
van Sambeek JW and G Rink (1981) Annual Report of the Northern Nut Growers Assn 72: 100–107
Von Althen FW (1976) Ten-year results of thinning and fertilizing of a pole-sized black walnut plantation. Report #0-X-245, Canadian Forestry Service, 17 pp
Weinbaum SA, Muraoka TT, Gatlin PB and Kelley K (1990) Utilization of fertilizer N by walnut trees. In: Walnut Research Reports, compiled by The Walnut Marketing Board, California, pp 234–243
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Jones, J.E., Garrett, H.E., Haines, J. et al. Genetic selection and fertilization provide increased nut production under walnut-agroforestry management. Agroforest Syst 29, 265–273 (1995). https://doi.org/10.1007/BF00704873
Issue Date:
DOI: https://doi.org/10.1007/BF00704873